New Moon of Saturn Discovered |
| Written by spacetravel.org | |||
| Thursday, 02 June 2005 20:51 | |||
 On May 10, 2005, NASA reported that the Cassini spacecraft has confirmed the discovery of the second moon existing within Saturns rings. The newly discovered moon, provisionally named S/2005 S1, is hidden in a gap in Saturns outer A ring. The moon was first seen in a time-lapse sequence of images taken on May 1, 2005. A closer view, allowing measurements of the moons size and brightness, was obtained on May 2. The new moons orbit is approximately 136,505 kilometers from the center of Saturn. It is not yet known whether the orbit is elliptical or circular.
Imaging scientists had predicted the new moons presence and its orbital distance from Saturn after a set of peculiar spiky and wispy features was seen in the Keeler gaps outer edge in July 2004. The Keeler gap is a 42-kilometer-wide gap in the A ring, approximately 250 kilometers from the ring's outer edge. Dr. Carl Murray, imaging team member from Queen Mary, University of London, says the effect of the moon on surrounding ring material will enable the moons mass to be determined. An estimate of the mass, along with a measure of its size, will tell us whether it is dense or porous. This will then provide information about how it was made and its history. The first, and only other moon to have been found within Saturns rings is Pan, which orbits the Encke gap. The Encke gap is a perceived gap within the A ring, starting 133,580 kilometers from Saturns center and extending another 325 kilometers. Pan is 16 miles across. All of the other moons exist outside the main ring system. Prometheus and Pandora, discovered by Voyager I in 1980, are shepherd satellites of the F ring, constraining the extent of the F ring through gravitational forces. The F ring is a narrow ring that was discovered by Pioneer 11 in 1979. Atlas, also discovered by Voyager I in 1980, seems to be a shepherd satellite of the A ring.
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